Force save changes when Enter is pressed for the controls with buffered updates.

chrome/browser/resources/print_preview/settings/copies_settings.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 cr.define('print_preview', function() {
   'use strict';
 
   /**
    * Component that renders the copies settings UI.
    * @param {!print_preview.ticket_items.Copies} copiesTicketItem Used to read
@@ skipping 57 matching lines @@
         this.getChildElement('button.decrement').disabled = true;
       }
     },
 
     /** @override */
     enterDocument: function() {
       print_preview.Component.prototype.enterDocument.call(this);
       fadeOutOption(this.getElement(), true);
       this.tracker.add(
           this.getChildElement('input.copies'),
+          'keydown',
+          this.onTextfieldKeyDown_.bind(this));
+      this.tracker.add(
+          this.getChildElement('input.copies'),
           'input',
           this.onTextfieldInput_.bind(this));
       this.tracker.add(
           this.getChildElement('input.copies'),
           'blur',
           this.onTextfieldBlur_.bind(this));
       this.tracker.add(
           this.getChildElement('button.increment'),
           'click',
           this.onButtonClicked_.bind(this, 1));
@@ skipping 73 matching lines @@
       var newValue =
           parseInt(this.getChildElement('input.copies').value) + delta;
       this.copiesTicketItem_.updateValue(newValue + '');
     },
 
     /**
      * Called after a timeout after user input into the textfield.
      * @private
      */
     onTextfieldTimeout_: function() {
+      this.textfieldTimeout_ = null;
       var copiesVal = this.getChildElement('input.copies').value;
       if (copiesVal != '') {
         this.copiesTicketItem_.updateValue(copiesVal);
       }
     },
 
     /**
+     * Called when a key is pressed on the custom input.
+     * @param {Event} event Contains the key that was pressed.
+     * @private
+     */
+    onTextfieldKeyDown_: function(event) {
+      if (event.keyCode == 13 /*enter*/) {
+        if (this.textfieldTimeout_) {
+          clearTimeout(this.textfieldTimeout_);
+        }
+        this.onTextfieldTimeout_();
+      }
+    },
+
+    /**
      * Called when a input event occurs on the textfield. Starts an input
      * timeout.
      * @private
      */
     onTextfieldInput_: function() {
       if (this.textfieldTimeout_) {
         clearTimeout(this.textfieldTimeout_);
       }
       this.textfieldTimeout_ = setTimeout(
           this.onTextfieldTimeout_.bind(this), CopiesSettings.TEXTFIELD_DELAY_);
@@ skipping 18 matching lines @@
       this.collateTicketItem_.updateValue(
           this.getChildElement('input.collate').checked);
     }
   };
 
   // Export
   return {
     CopiesSettings: CopiesSettings
   };
 });